Question

The atomic mass of the middle element was approximately equal to the mean of the atomic masses

of other two elements.  What are these elements know as​

Answer 1

Answer:

After inserting a chart , the design and format Tab appear on the Ribbon under the________contextual tab

Explanation:

After inserting a chart , the design and format Tab appear on the Ribbon under the________contextual tab

Answer 2

Answer:

Dobereiner's Triad - definition

He found that the atomic mass of the middle element was approximately equal to the arithmetic mean (average) of the atomic masses of the other two elements of that triad when they are arranged in their increasing order of atomic mass, e.g., Li, Na, K.

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